As a single footstep will not make a path on the earth, so a single thought will not make a pathway in the mind. To make a deep physical path, we walk again and again. To make a deep mental path, we must think over and over the kind of thoughts we wish to dominate our lives.

Henry David Thoreau

We have forty million reasons for failure, but not a single excuse.

Rudyard Kipling

As one digs deeper into the national character of the Americans, one sees that they have sought the value of everything in this world only in the answer to this single question: how much money will it bring in?

Alexis de Tocqueville

The ideal reasoner, he remarked, would, when he had once been shown a single fact in all its bearings, deduce from it not only all the chain of events which led up to it but also all the results which would follow from it.

Arthur Conan Doyle

The strength of the Constitution lies entirely in the determination of each citizen to defend it. Only if every single citizen feels duty bound to do his share in this defense are the constitutional rights secure.

Albert Einstein

It has always been my practice to cast a long paragraph in a single mould, to try it by my ear, to deposit it in my memory, but to suspend the action of the pen till I had given the last polish to my work.

Edward Gibbon

The journey begins with a single step, but the memories and experiences last a lifetime.

I am so clever that sometimes don’t understand a single word of what I am saying.

Oscar Wilde

No amount of experimentation can ever prove me right a single experiment can prove me wrong.

Albert Einstein

I do not take a single newspaper, nor read one a month, and I feel myself infinitely the happier for it.

Thomas Jefferson

Mankind is not a circle with a single center but an ellipse with two focal points of which facts are one and ideas the other.

Victor Hugo

Masterpieces are not single and solitary births; they are the outcome of many years of thinking in common, of thinking by the body of the people, so that the experience of the mass is behind the single voice.

Virginia Woolf

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.

Galileo Galilei